This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. RNA trafficking is a complex process whereby specific RNAs are localized to particular subcellular compartments. Through a variety of in vivo and in vitro techniques we have delineated a molecular interaction map describing the RNA trafficking system in neural cells. We have measured quantitative parameters for each molecular interaction in RNA trafficking using surface plasmon resonance analysis in vitro and fluorescence correlation spectroscopy (FCS) and in live cells. Quantitative parameters are used in Virtual Cell models of RNA trafficking.